Heat Transfer Aspects in Boundary Layer Row Problems

Abstract

Academic curiosity and technologi cal appli ca tions have generated considerable interest of researchers towards non-Newtonian rheology. In recent years, numerous examinations have been reported on non-Newtonian fluids due to their generous and treasured utility in industrial produ ction mechanism, power engineering, petroleum production and broad spectrum chemical processes. Non-Newtonian fluids are diversified classifically into various models in view of the fact that a single constitutive relation is inadequate to illustrate the complete characteristics of all these fluids. There models are primarily characterized as visco-inelastic fluids, visco-elastic fluids, polar fluids, anisotropic fluids and fluids with micro-structure. Among these the paramount subclass of non-Newtonian fluid is visco-inelastic fluids and pseudoplastic fluids. Fluids in which the apparent viscosity reduces with increasing deformation rate are call ed pseudoplastic fluids. These fluids delineate the shear thinning properties. In many practical applications the boundary layer flow of pseudoplastic fluids takes place in melts of high molecular weight polymers, emulsion coated sheets like photographic films, solutions and extrusion of polymer sheets etc. The magnetohydrodynamic flows of electrically conducting fluid are significant in several processes of geophysics, astrophysics, engine.ering and other industrial areas. Influence of heat generation/absorption is encountered in underground disposal of radioactive waste materials, disassociating fluids from packed bed reactors, storage of food stuffs and heat removal from nuclear fuel debris. The phenomenon of diffusion arises extensively in fluid flows due to variation in buoyancy forces . These forces lead to temperature and density variation which as an outcome causes diffusion among heavier and lighter fluid molecules. From recent developments ·in modern technology it is empirica lly proved that diffusion of energy is generated due to the gradient among molecules concentration whereas diffusion of species is produced due to temperature slope. Thus the analysts have defined these diffusions terminologically as thermo diffusion (Dufour) and diffusionthermo effects (So ret). Literature review about Willaimson, Casson, and Prandtl fluid models under the impact of various physical parameters is given in chapter O. In chapter I, the numerical investigation thermally stratified Williamson fluid flow over a stretching cylinder is discussed. Finite difference solution of present model is attained by implementing Keller Box method. The governing partial differential equation of Williamson fluid is converted into an ordinary differential equation by using similarity transformations along with boundary layer approach. The effects of different pertinent parameters on velocity profile are thoroughly examined through graphs and tables. The contents of this chapter are published in Results in Physics 7(2017)690- 696. The Combined effects of variable thermal conductivity and MHO flow on pseudoplastic fluid over a stretching cylinder is examined in chapter 2. The boundary layer partial differential equations are converted into ordinary differential equations by using suitable transformations. The non-linear ordinary differential equations are solved by using implicit finite difference Kellet; box technique. The effects of several pertinent parameters on velocity, temperature and concentration profiles are deliberated graphically. The behavior of skin friction coefficient and Nusselt number are examined. The contents of this chapter are published in An international Journal of Information Science Letters 5(2016)11-19. Chapter 3 is devoted to examine the Computational and theoretical aspects of pseudo-plastic fluid flow over an exponential surface. In this chapter heat transfer mechanism is discussed by using Cattaneo Christove heat flux. The boundary layer partial differential eq uations are transformed into ordinary differential equations by using group theory transformations. The obtained ordinary differential equations are solved numerically by using shooting method . The influence of dimensionless physical parameters on velocity and temperature profiles as well as skin friction coefficient and local Nusselt number are presented graphically. Comparison has been made with literature. Chapter 4 inspects the numerical investigation of Casson fluid model over an exponentially stretching sheet in the presence magnetic field effects. Cattaneo-Christov heat flux model which amended form of Fourier's law is used to explore the heat transfer phenomena. The governing equations representing non-linear problem are presented and transformed into self-similar form by using similarity approach. The modified non-linear problem is solved numerically by using shooting method. The effects of relevant physical parameters on velocity and temperature profiles are taken into consideration. The contents of th is chapter are published in Neural Computing and Applications DOl 10.1007/s00S21-016-2832-4. In chapter 5, MHD boundary layer flow of Prandtl nano fluid over a stretching sheet is obtained. The effects of double diffusion are also accounted. The governing boundary layer equations regarding the flow is converted into an ordinary differential equation using similarity transformations, which is then solved numerically by applying Shooting method. The contents of this chapter are published ill Results in Physics 7(2017)470-479 . Chapter 6· is focused to examine the heat and mass transfer effects of viscous fluid over a rotating cone. Heat transfer features are explored by using Dufour and Soret effects whereas mass transfer mechanism is conducted in the presence of chemical reaction. The requisite partial differential equations are metamorphosed into ordinary differential equations by using similarity transformations. The obtained ordinary differential equations are solved by using Homotopy analysis method. The physical behavior of non-dimensional parameters for momentum and temperature and concentration profiles is deliberated · through graphs. The variation of skin friction coefficient, local Nusselt number are mass flux coefficient is also visualized. The contents of this chapter are published in AlP Advances 6125125 (2016).